acrylic bowing, now what?

Double J · Dec 27, 2016

As the title says I just noticed a pretty good bow in the back of my tank yesterday. It looks like its from the skimmer and hob filter hanging on the back of the tank. I will try to get a picture tonight. Im just wondering how much bowing is ok? The tank has a lifetime warranty on it, but I was also considering drilling it and adding a sump, although not sure how well this would work with the bowing.
Anyone have experience with this?
Thanks

jsker · Dec 27, 2016

No bowing should be happening, this could mean that a failure is eminent. If you are going to go sump this is the time to do it but consider that the acrylic is now in a weakened state. How large is the tank? Call the manufacture.

Double J · Dec 27, 2016

jsker said:
No bowing should be happening, this could mean that a failure is eminent. If you are going to go sump this is the time to do it but consider that the acrylic is now in a weakened state. How large is the tank? Call the manufacture.

its a 50 gal 36" long, less then a year old. I will get in contact with them!

Elementalj · Dec 27, 2016

Double J said:
its a 50 gal 36" long, less then a year old. I will get in contact with them!

ASAP!!!!

redfishbluefish · Dec 27, 2016

Note drilling the tank most likely kills the warranty.

Rjramos · Dec 27, 2016

How thick is the acrylic sheet that was used to manufacture. My 1st reef tank was a 55 gal plexiglas Tenecor. It was made in 1/4"or 5/16" plexiglass and bowed like crazy! I got scared and replaced it with custom glass tank. Also had scratches due to trying to get coralline off the glass. That was about 1995, never had or recommended plexiglas for reef since.

Elementalj · Dec 27, 2016

redfishbluefish said:
Note drilling the tank most likely kills the warranty.

And don't tell them you had ANYTHING hanging off the back!

Elementalj · Dec 27, 2016

Matter of fact, I'd delete this entire thread as soon as you've reached anyone!

Double J · Dec 27, 2016

Thanks all! yes I know drilling will void the warranty, but I have read online they wont cover the tank unless it is leaking. Not sure I want to wait for it to leak.

Double J · Dec 27, 2016

Rjramos said:
How thick is the acrylic sheet that was used to manufacture. My 1st reef tank was a 55 gal plexiglas Tenecor. It was made in 1/4"or 5/16" plexiglass and bowed like crazy! I got scared and replaced it with custom glass tank. Also had scratches due to trying to get coralline off the glass. That was about 1995, never had or recommended plexiglas for reef since.

Looks to be 1/4" to me

Rjramos · Dec 27, 2016

Double J said:
Looks to be 1/4" to me

A smaller tank like nano cube size usually does fine. Larger tanks 1/2" thickness or more. Any medium to large tank in 1/4" is gonna bow with time regardless of hang on the backs, light hood on top, drilling, etc.

Double J · Dec 27, 2016

Looking at it again today the bow is only 1/8" at most just in the center where it has less support for hob filter. Attached pic is my fix, hope it works. I was going through some papers and never sent in the warranty card, says to do it in 30 days. That was a year ago, whoops

cromag27 · Dec 27, 2016

1/8" bow can be acceptable with acrylic tanks. How long have you had it set up? how tall is it?

Rjramos · Dec 27, 2016

Mine bowed for a long time, but never leaked. It did get worse overtime, and then I replaced it. Got scary noticeable.[emoji51]

Elementalj · Dec 27, 2016

Prop up the filters? Got something sturdy enough to place under the filters to relieve the stress on the acrylic?

c.poindexter · Dec 28, 2016

I actually just went through all of this about 2 months ago. My acrylic tank had been set up for 5 years and going strong. About 9 months ago I noticed the back of the tank having a bow to it. Did some research and people said it could be normal depending on the thickness. The thickness of my back was 1/4" and the tank was a 75 gallon. I kept an eye on it and nothing seems to change. Needless to say I came home one day to a split tank and about 40 gallons of water in the carpet.

Kungpaoshizi · Dec 28, 2016

c.poindexter said:
I actually just went through all of this about 2 months ago. My acrylic tank had been set up for 5 years and going strong. About 9 months ago I noticed the back of the tank having a bow to it. Did some research and people said it could be normal depending on the thickness. The thickness of my back was 1/4" and the tank was a 75 gallon. I kept an eye on it and nothing seems to change. Needless to say I came home one day to a split tank and about 40 gallons of water in the carpet.

What was the brand?

What's the brand of the OP>?

Double J · Dec 28, 2016

Kungpaoshizi said:
What was the brand?

What's the brand of the OP>?

it is a sea clear 50 gallon 36" x15" x 21" high.

cromag27 · Dec 28, 2016

I've built several tanks that size. even with a full euro I was using 1/2" acrylic.

Double J said:
it is a sea clear 50 gallon 36" x15" x 21" high.

Rjramos · Dec 28, 2016

cromag08 said:
I've built several tanks that size. even with a full euro I was using 1/2" acrylic.

I found out that a 1/4" acrylic tank doesn't work out well a long time ago! The bowing and micro-stress cracks along the joints, the scratches trying to get coralline off, and yes the dangers and damage done by one of these tanks blowing up! Why and how these manufacturers are even building them is beyond me. I mean, property damage or even someone getting hurt, the liability.???[emoji848]